FIG. 12 is a block diagram of a conventional inertial force sensor. As shown in FIG. 12, conventional inertial force sensor 1 includes detection element 2, detection circuit 3 for detecting the amount of inertia corresponding to an inertial force applied to detection element 2, low-pass filter 4 connected to the output side of detection circuit 3, and correction circuit 5 for correcting the output of low-pass filter 4. Correction circuit 5 includes correction amount storage unit 6 to storing a correction amount from outside and correction unit 7 connected to the output side of low-pass filter 4 and to the output side of correction amount storage unit 6. Correction unit 7 corrects the output value of low-pass filter 4 based on the correction amount stored in correction amount storage unit 6.
Inertial force sensor 1 is required to output zero or a predetermined reference value when having no inertial force is applied thereto. When an inertial force is applied, sensor 1 is required to output an output corresponding to the inertial force. To achieve this function, before the shipping of conventional inertial force sensor 1 from the factory, a measurement is performed to determine the output deviation due to the production tolerance of detection element 2, and the output offset (initial offset) due to the electrical offset of detection circuit 3. Then, a correction amount is stored in correction amount storage unit 6.
An example of a conventional technique related to the present invention is shown in Patent Literature 1.
However, conventional inertial force sensor 1 shipped with the stored correction amount still has a problem that an output offset may be caused, for example, when a stress is applied to detection element 2 even if no inertial force is applied.